Hi Dave. Interesting - can you elaborate a little for me. What application method? Application rate? What size is your pond? I'd really like to hear more of your comments/experience with it. I must say that when I had a well dug, they used a little bentonite around the small dug out area where the well pipe comes up out of the ground. It's just a small area. only about two feet in diameter and about a foot deep. But that little area holds water big time, so in theory it looks like it would work fine, but of course that little deal doesn't cost a thousand bucks either....